Tutorial EP12—Plasmonics, Metamaterials and Metasurfaces for Manipulating Light at Nanoscale

The emerging materials research for optical and photonic devices is critical for aligning with current trends in science and technology. An in-depth discussion of the various material options that have sprung up and continue to excite researchers with an accelerating trend put a high demand on exploring a new wave of photonic applications. Plasmonic nanostructures and optical metamaterials control the propagation of light in subwavelength dimensions, enabling novel material properties and optoelectronic devices. This tutorial aims at highlighting strategies to broadly address the grand challenges in plasmonics and metamaterials, spanning novel synthetic methods, advanced nanostructure characterization, and ultimate integration of these advances into diverse areas such as energy conversion, flat optical components and nanoscale optoelectronic devices. This tutorial session will provide the platform to bring together scientists and engineers from a variety of materials research disciplines and engage them in active discussions toward shaping future plasmonic and two-dimensional materials, metamaterials and their nanoscale application.

8:30 am—Two-Dimensional Materials Optics and Photonics
Linyou Cao, North Carolina State University

This tutorial gives a comprehensive introduction for the optics and photonics of atomically thin two-dimensional (2D) materials, in particular, 2D semiconductors like transition-metal chalcogenide materials. It will mainly focus on the unique optical properties and photonic applications enabled by the strong exciton binding energy in 2D materials, which cannot be obtained with other material systems. The tutorial will start with the basic physics of excitons in 2D materials, followed by a brief introduction for cutting edge research such as different phases of excitons and exciton condensation. Next,  the tutorial will cover the exotic light–matter interaction of 2D materials that are related with the remarkable excitonic properties, including absorption, emission, scattering and electrically tunable refractive index. It will also cover the novel strategies for the manipulation of light–matter interactions with 2D materials, such as electrical and magnetic fields, cavities, mechanical forces and substrates.

10:00 am BREAK

10:30 am—Achieving the Ultimate Limits of Plasmonic Enhancement
Reuven Gordon, University of Victoria

Plasmonic enhancement has had remarkable success in optical coupling to the nanometer scale, enabling feats such as Raman spectroscopy with single molecule sensitivity. Here it is described how much greater enhancements are possible in the near future by combining the gains of plasmonic resonances, directivity, sub-nanometer gaps and permittivity near zero materials. The physics behind each of these phenomena will be reviewed in this lecture. By pushing the limits of plasmonic enhancement, it is expected that the community will gain a greater appreciation of how physical phenomena such as non-locality, surface scattering and quantum tunneling each play a role in determining the ultimate performance. The impact of these additional effects will also be discussed. The pursuit of such extraordinary enhancements promises to bring new physics such as peering into the world of quantum optomechanics. I will discuss new applications such as quantitative single-molecule Raman spectroscopy and low photon number nonlinear optical switching.

1:30 pm—Tailoring Plasmonic Materials for Improved Optoelectronic Devices
Jeremy N. Munday, University of Maryland

Plasmon excitation can result in highly confined optical fields near interfaces. This property has been exploited in devices ranging from photodetectors and solar cells to electrochemical cells, sensors, and color pixels. For such devices, there are tradeoffs between beneficial photon absorption, parasitic optical loss, and electrical conductivity. Further, the optical and electrical properties depend critically on the materials used (metals, alloys, ceramics, highly-doped semiconductors, low- dimensional materials, etc.). In this tutorial, we will discuss a variety of device applications and the associated material tradeoffs. Topics will range from fundamental materials properties, how they can be tuned, effects of hot electrons in plasmonic materials, and future outlooks for such devices.

3:00 pm BREAK

3:30 pm—Nanophotonic Converters and their Materials for Thermal Devices and Molecular Sensing Applications
Tadaaki Nagao, National Institute for Materials Science

Plasmonic perfect absorbers can exhibit nearly 100% absorptivity at desired wavelengths, and also emit light at the same wavelengths when they are heated. Their use has been successfully demonstrated, such as in wavelength-selective infrared thermal emitters and molecular vibrational sensors. In this seminar, I will summarize some recent studies in our group on the perfect absorbers based on the metal-insulator-metal structures, Fabry–Pérot or other similar types of cavity structures as well as 2D patterned structures. Some of the fabricated mid-infrared perfect absorbers exhibit narrowband resonant absorption as narrow as 22 nm with efficiency higher than 97%. We introduce some applications of these devices such as selective thermal emitters operated above 1273 K, selective surface-enhanced vibrational spectroscopy for high-sensitivity molecular sensing, and wavelength selective IR detectors in combination with pyroelectric, thermoelectric and bolometer devices.